The interaction between hypoxanthine (HX) and silver nanoparticles (NPs) is studied with electrochemical technique, together with UV-vis spectroscopy (UV-vis) method. Experimental results reveal that the usually silent carbonyl will be activated by the interaction between HX and silver NPs, which leads to a new electrochemical reduction route for HX. Meanwhile, a nonenzymatic detection method for HX is proposed. The reductive peak current is linear to the concentration of HX in the range of 1.0 x 10(-6) to 1.0 x 10(-5) mg/mL (r = 0.998) and 1.0 x 10(-5) to 1.0 x 10(-4) mg/mL (r = 0.999), respectively. The detection limit is 1.0 x 10(-6) mg/mL. It is much more sensitive than the previous reported methods, which proves to be a potential way for HX measurements. (c) 2005 Elsevier B.V. All rights reserved.